Air conditioner condensate disposal system



H. DURDLE July 24, 1962 AIR CONDITIONER CONDENSATE DISPOSAL SYSTEM 2Sheets-Sheet 1 Filed March 24, 1961 INVENTOR Horold Durdle wwfwATTORNEYS July 24, 1962 H. DURDLE AIR CONDITIONER CONDENSATE DISPOSALSYSTEM 2 Sheets-Sheet 2 Filed March 24, 1961 ATTORNEYS a condenser.

United States Patent 3,045,449 AIR CONDITIONER CONDENSATE DISPOSALSYSTEM Harold Durdle, Greenville, Mich., assignor to Hupp ;Cor-Poration, Cleveland, Ohio, a corporation of Virginia Filed Mar. 24,1961, Ser. No. 98,079 i 4 Claims. (Cl. 62279) This invention relates toair conditioner apparatus and more particularly to apparatus fordisposing of the condensate water accumulated in the operation of airconditioners. I

As used herein, the term air conditioners refers to devices which areeffective to cool the space served by the unit-or to selectively cool orheat such space. In general such units include a pair of seriesconnected coils, one in heat exchange relation with the indoor air andthe other in heat exchange relation with the outdoor air. When thedevice is used for cooling, the indoor coil functions as an evaporatorand the outdoor coil functions as In certain cases, the refrigerantcircuit is provided with gas reversal valves to reverse the functions ofthe coils when indoor heating is required.

When units of this type are' operated, substantial amounts of watercondense on the evaporator coil and must be removed. In air conditionersoperating on the cooling cycle, the water which condenses on the indoorevaporator is conducted to a pan positioned adjacent the fan associatedwith the outdoor condenser coil. The water is picked up by a slingerring carried by the fan and is entrained in the air stream passing overthe condenser coil where it is evaporated. This system has proved quiteeffective in practice since it not only produces rapid removal of thewater but also increases the efiiciency and capacity of the condenser.

However the utilization of the slinger ring has several disadvantages.For example, it increases the cost of the fan, it increases the powerrequired to drive the fan and since the slinger ring must enter theliquid, it produces a source of additional annoying noise. Further, itis not suit able for use when the unit is operated at sub-freezingtemperatures. Under these conditions, freezing of the condensate watermay either stall or damage the fan.

Also the slinger ring construction is limited in application to thepropeller type fan which, in many cases, cannot move a suflicientvolumeof air to assure operation of the unit at rated capacity. Forexample, in the so-called through-the-wall units, it is often necessaryto move the air through relatively restricted passages. In these cases,it is necessary to employ a centrifugal blower to obtain the necessaryair movement.

In recognition of the fact that conventional slinger ring constructionscannot be used with such blowers, alternate condensate disposal systemshave been proposed for such blowers, .an example of such a constructionbeing shown in United States Patent 2,776,554. This and similarproposals are subject to the same limitations as conventional slingerrings, since the water disposal apparatus is carried by the rotatingblower member and must physically enter the condensate water thusproducing the same problems of cost, balance, noise and freezing as areencountered in the operation of conventional propeller fan slingerrings.

With these considerations in mind, it is the principal purpose andobject of the present invention to provide,

novel apparatus for disposing of condensate water in an air conditionerunit equipped with a centrifugal blower which is substantially noiselessin operation and which is not adversely aifected by the freezing of thecondensate Water. a

It is a further object of the present invention to provide, a

3,045,449 Patented July 24, 1962 It is also an object of the presentinvention to provide novel systems including a centrifugal blower forremoving condensate water, the apparatus being so constructed that therotating blower wheel does not enter the body of 'the water thuspermitting normal operation of the blower in sub-freezing temperatures.

It is an additional object of the present invention to provide improvedcondensate disposal systems which eliminate the need for modification ofthe blower wheel and the need for installation of water pick-upapparatus on the wheel itself, thus reducing the cost of the unit andthe problems of balancing and noise associated with prior units.

It is a further object of the present invention to provide improvedcondensate removal apparatus in which all of the water pick-up apparatusis stationary and which thus need not be made to the close tolerancesrequired in prior units to assure the balance of blower wheels or fanmembers rotating at a relatively high speed.

In attaining these and other objects, the present invention provides, inassociation with a centrifugal blower, a water delivery system whichoperates automatically upon the establishment of a moving air currentproduced by the blower to cause the condensate water to move from a drippan position at the bottom of the blower housing upwardly into a regiondirectly in the path of the moving air current where it is entrained bythe air current for delivery to a condenser or other point of disposalas required. The movement of the water is produced solely by thepressure dilferentials produced by operation of the blower and theblower wheel is at all times completely out of contact with thecondensate water.

Additional objects and advantages will become apparent as thedescription proceeds in connection with the accompanying drawings inwhich:

FIGURE 1 is a top plan view of an air conditioning apparatus embodyingthe present invention with the top cover removed to show interiordetails;

FIGURE 2 is a vertical section taken along lines 22 of FIGURE 1; and

FIGURE 3 is a horizontal section taken along line 33 of FIGURE 2.

The condensate removal system of the present invention will .bedisclosed as applied to a self-contained unitary air conditoning unit ofthe so-called through-thewall type adapted to be mounted in a wallopening of a building. Except for the condensate removal system, theunit is of essentially conventional construction.

The air conditioning assembly is of generally rectangular configurationand is adapted to be positioned in the wall 20 of the building in amanner to dispose its front surface 22 projecting slightly into thebuilding and to dispose its rearward surface 24 projecting a slightdistance outwardly of the building. The principal components of theassembly are the evaporator 26which extends -of the air conditionerunit. The pan 36 has an annular lip 37 to form a water receptacleofsubstantial depth, ie one inch.

In accordance with conventional practice, the output side of thecompressor is connected by a conduit 38 to the inlet side of thecondenser, the outlet side of the condenser is connected by a capillarytube 40 to the inlet side of the evaporator and the outlet end of theevaporator is connected by a suction line 42 to the inlet side of thecompressor to form a closed refrigerant circuit. The blower 34 is of thecentrifugal type and comprises a housing having a convolute wall 44, aside wall 45 having a single side air inlet opening 46 and animperforate side wall 47, and an air outlet throat formed between theterminal portions 48 and 50 of the convolute housing wall 44.

A centrifugal blower wheel 52 is mounted within the housing on a driveshaft 54 driven by a fractional horsepower motor 56 carried by anannular strap 58 supported from the side wall 45 of the housing by threemounting tabs 60, 61 and 62. The motor shaft 54 extends through theadjacent imper-forate side walls of the blower assemblies 34 and 32 intothe latter where it supports a second blower wheel 64 which rotateswithin the blower assembly 32 which is of essentially the sameconstruction as the blower unit 34.

A side air inlet opening 66 of the blower assembly 32 is positionedbehind the evaporator and its outlet throat 68 is positioned to directthe air issuing therefrom between partitions 70 and 72 to an air outletgrill assembly indicated generally at 74 at the front of the airconditioner between the end of the evaporator and the end of the airconditioner unit.

The blower wheel 52 draws air inwardly over a portion of the condenserthrough the single side air inlet opening 46 and delivers it to theregion of the compressor at the rear of the partition 70, the airfinally exiting from the apparatus through the adjacent portion of thecondenser as shown by the arrows 76.

The apparatus thus far described is provided with controls forenergizing and de-energizing the compressor 30 and the blower motor 56automatically in response to temperatures or manually to provideventilation. Since these controls are in all respects conventional, theyhave been omitted for clarity and will not be described further here.

In the operation of the unit, the relatively warm humid air passing overthe chilled evaporator coils 26 causes a substantial amount of moistureto condense on the evaporator coils which, after a short period ofoperation, drips into the base pan 36. As best shown in FIGURE 2, thelowermost portion of the condenser blower housing 44 extends into thebottom of the base pan 36. The side wall 45 is provided with an opening78 to permit water to enter the lowermost portion of the casing. To

facilitate the flow of water into the blower housing and to establish apumping action, a transverse baffle 80 extends inwardly a short distancefrom the side wall 45 of the blower housing just upstream of the opening78. This bafiie establishes a low pressure region in this area whicheffectively draws the water into the blower housing. It ischaracteristic of this type of blower that the air issuing through thethroat is delivered in a relatively thin stream closely adjacent theinner surface of the volute housing portion, the velocity of the airbeing greatest in the region immediately adjacent the inner surface ofthe housing. The high velocity air movement in this region is effectiveto sweep the water in the bottom of the blower housing upwardly over theinclined blower section 82 into a trough 84 which, as shown in FIG- URES2 and 3, extends horizontally across the outlet of the blower just belowthe lower lip 50.

As shown in FIGURE 3, one end of the trough projects beyond the sidewall 45 of the blower housing and is provided with a rearwardlyextending fitting 86 connected to a tube 88 which extends along the sidewall 45 of the blower housing 44. The rearward end of the tube 88 isbent to extend inwardly through the side wall 45 preferably directlybelow the axis of the blower and above the water inlet opening 78. Theend of the tube 88 is cut away as at 90 to provide an outlet opening ofsubstantial area facing away from the air stream. The flow of air aroundthe imperforate portion of the end of the tube creates a low pressureregion at the outlet opening thus causing water to flow through the tube-where it is entrained in the air stream and is carried in the form ofsmall droplets over the relatively hot condenser where it is evaporated.

Actual experience has shown that the rate at which the water is removedby the novel structure just described exceeds the rate at which it isdeposited in the drip pan by the evaporator. The accumulation of waterin the base pan 36 is held to a minimum thus substantially eliminatingthe possibility that condensed moisture will be picked up andre-circulated into the room. Thus the efficiency of the unit inde-humidifying the interior air is substantially increased. A correlatedadvantage is derived from the delivery of the moisture in fine dropletsto the condenser thus assuring that the evaporation of the water at thecondenser will be substantially complete. Evaporation of this waterexerts a substantial cooling effect on the condenser thus increasing itseffective capacity.

As stated above, it is desirable under certain conditions to operate theblower when the ambient outdoor temperature is below 32 F. For example,an air conditioner unit may be operated under these conditions toprovide ventilation. Also, the blower is operated at sub-freezingtemperatures when indoor heating is required. In this case it isnecessary to modify the unit by the addition of since the periphery ofthe blower is always a substantial distance above the level of water orice in the base pan 36.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning and range of equivalency of theclaims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1. A condensate disposal apparatus for air conditioners comprising; awater collector pan, a centrifugal blower I having a blower wheel and ahousing, said housing having a side air inlet opening and a curvedperipheral wall having its lowermost portion essentially tangential tothe bottom of said pan, said wall having an unobstructed portion curvingsmoothly upwardly from said floor and terminating not substantiallyabove the level of said pan to form with the opposite end of saidperipheral housing wall an essentially horizontal air outlet, meansdefining an opening in said housing to permit water in said pan to flowinto said lowermost portion of said housing, an upwardly open collectortrough positioned adjacent the lower edge of said outlet opening andextending entirely across said outlet opening whereby when said bloweris in operation water is moved by the flow of air toward and throughsaid outlet opening, a portion of said water being delivered to saidtrough, conduit means connecting the interior of said trough to theinterior of said blower housing, the terminal portion of said conduitmeans being positioned substantially below said blower wheel anddirectly in the air stream flowing toward said outlet whereby waterissuing from said terminal portion is entrained in said air stream.

2. The combination according to claim 1 together with a transversebafiie in said housing immediately upstream of said opening, said bafliebeing effective to create a low pressure region adjacent said opening topromote the flow of water therethirough.

3. The combination according to claim 1 wherein said terminal portion ofsaid conduit means extends substantially parallel with the axis of saidblower and is provided with an elongated opening facing toward saidoutlet.

4. An air conditioner assembly comprising a rectangular base pan, anevaporator extending along one edge of said base pan, a condenserextending along the opposite edge of said pan, first and second blowershaving convolute housings-mounted in side-by-side relation between saidevaporator and said condenser, a blower motor mounted on one of saidhousings, blower wheels positioned in the respective blower housings,means drivingly connecting said motor with each of said blower wheels,said first blower being arranged to draw air over said evaporator andsaid second blower housing having a side air inlet opening positionedopposite a portion of said condenser whereby said second blower isarranged to draw air inwardly over said portion of said condenser andhaving an essentially horizontal air outlet opening, means for directingthe air delivered by said second blower in an essentially horizontalpath over another portion of said condenser, means defining an openingin the housing of said second blower to permit condensate accumulated insaid base pan to flow into said housing, an upwardly open troughextending across the outlet of said second blower housing into whichsaid condensate is moved by the air passing through said second blowerhousing, and conduit means conducting said condensate from said troughinto the air stream issuing from said second blower housing in a regionbelow the blower wheel therein for entrainment in said air stream.

References Cited in the file of this patent UNITED STATES PATENTS2,134,349 Weiland Oct. 25, 1938 2,417,743 Eberha-rt Mar. 18, 19472,710,510 Roseman June 14, 1955 2,941,381 Eberhart June 21, 1960

